Motor Age Garage

Search Autoparts/Motorage/Motor-age-garage/

Motor Age Garage: When customers need us — and we need them

Friday, June 1, 2018 - 07:00
Print Article

The 99 Mazda 3.0L, a Caravan and a Freestar

Motor Age Magazine Want more ? Enjoy a free subscription to Motor Age magazine to get the latest news in service repair. Click here to start you subscription today.

Pass all the ASE tests for 30% less!



Nick is one of my guys, and he told me his truck was losing water and running hot — it had a leaking hose, but he had added water and had driven it until he had damaged it to the point that the compression was pushing its way into the coolant. Blown gaskets prevailed, and it was his only ride, so we got started yanking the heads off. If he was fortunate, head gaskets would be all he’d need, but he wasn’t fortunate — as it was, he needed a cylinder head, and that ran the bill up a bit. He finished the truck, paid the bill, and got his ride back.

The 99 Mazda got hot enough to crack this head, and a new one was in order. A few hundred dollars later, the B3000 was back on the road, at least until its next breakdown.
After misfiring on a parasitic drain diagnosis the first time and replacing the BCM with a used one (which changed the odometer reading; we had to straighten that out) we finally caught the Caravan’s intermittent in the act and pinpointed the FCM in this TIPM as the problem. It was keeping the accessories fired up even after the door was opened..

The college owns a 2005 Dodge Caravan with nearly 200K on the clock, and that vehicle’s status changed from being driven every day to being driven about once a week, and a parasitic drain suddenly raised its ugly head. About half the time whenever a driver would obtain the keys to use that vehicle, the battery would be dead. With the PICO connected via an inductive clamp, we discovered a significant drain that evaporated when the accessory relay was removed, and when we’d remove that relay, we’d feel the “click” of the relay coil releasing — that relay was remaining energized constantly after it should have gone dark, and that was keeping the radio, power windows, etc. up and running even after the driver had exited the vehicle. It wouldn’t do this every time, but we caught it doing this during our diagnostics. On this vehicle, the front control module energizes the accessory relay, and that module is part of the TIPM — the smart fuse box, if you will. With the scan tool connected and the problem present, we saw no reason why the accessory relay should have been remaining energized, and we were lucky enough to find the right replacement TIPM for $100 at a local salvage yard. Game, set and match on that one.

The 2005 Freestar wasn’t overheating, but it was an occasional no-crank. We found that we could bypass the secondary terminals in the relay socket and the starter would spin, but that there was no juice at all making it from the ignition switch to the starter relay coil. The theft light wasn’t blinking and there were no related codes, so we checked connections between the ignition switch and the starter relay and found a time-corroded set of chalky terminals at TR sensor pin 12 that turned out to be interrupting the current to the relay coil. Had this been a high-current circuit, this oxidized terminal would have melted the connector. That one was an easy fix.

The Freestar’s TR sensor had a time-oxidized pin 12 – that was the reason for the stubbornly intermittent no-crank. There are pigtails and terminals to be had – at a cost. But that’s the best fix for a problem like this.

The 2004 Land Rover

A guy came to us with a 2004 Land Rover that was leaking brake fluid and had a no-blow problem with the A/C — the blower was dead, and one of my guys did some Googling, as young guys with smartphones are wont to do — it seems that half the people who owned a Rover of this generation had a dead blower motor and nobody seemed to know the root of the concern, but everybody was running overlays. With a desire to know why, we dug up the schematic. In the panel, the fuse was good, and power was passing through it, but when we finally found the blower relay (which was annoyingly difficult, but Identifix® has the information, albeit for an RHD vehicle), we discovered that there was no power at the relay common terminal — it had nothing to deliver to the blower motor.

This guy bought a Land Rover for a hunting truck. Not sure why he went so far out of his way to locate one of these, but he did. There aren’t many of these around here either.
Article Categorization
Article Details

< Previous
Next >
blog comments powered by Disqus