Speedometer and 4X4 On Light - Toyota Nation Forum : Toyota Car and Truck Forums

Smoke · 02-14-2005, 08:46 PM

Just got though changing out my engine, adding Downey headers and doing other mechanial repairs to the trans and transfer A340H, nothing internal. Both the speedometer and the 4X4 on light in the dash stopped working. Everything else works fine and 4WD is engaging. Trying to figure out what these two have in common that might be causing this problem. The light bulb is good. OD, ECT and AT Temp lights work!! Anybody got an idea?? These factory electrical diagrams leave alot to be desired!! Any suggestions will be appreciated!!

JETACO · 02-14-2005, 10:01 PM

hmm i would say check the fuse and make sure it isn't blown, check the one under the hood and underneath the dash

Smoke · 02-14-2005, 10:36 PM

Will do!! Know which one it is?? Gauge fuse is good!!

Smoke · 02-15-2005, 09:02 AM

I'm reading codes 14, 21 & 42. The 21 is explainable since the o2 isn't hooked up yet. The 14 IGF signal from igniter is not input to ECM for 6 consecutive ignitions & 42 SPD signal is not input to the ECM for at least 8 seconds during high load driving with engine speed between 2,750 rpm and 4,000 rpm are the ones that I can't explain!! Help needed can not make heads or tails from this FSM. Need something a shadetree mechanic can understand. As you can tell these computers aren't my cup of tea!! Open for suggestions that I can understand. All connection are in place as best I can see. Will get under there and hand check each one for good clean connection!! Thank you!!

JETACO · 02-15-2005, 09:06 PM

sounds good, i would get a test light and see which ones makes the light come on and which ones dont do anything. there are some new fuses out that light up when they are blown, so im asuming that you dont have those, try that and see what you get

Smoke · 02-18-2005, 08:04 AM

Found the problem on codes 14 & 42. Terminal SP1 at ECM wasn't grounging. Does anybody know where the transfer on indicator switch is located on the 94, 3.0, 4X4, Auto, A340H trans?

Smoke · 03-02-2005, 04:19 PM

Rid of all codes, speedometer working and still trying to find out what controls the 4WD indicator in dash. Bulb good, 4WD working and no ADD on vehicle. A340H auto. Has anyone got any idea if there is a switch that controls the indicator and where it might be??

peterng · 03-02-2005, 04:42 PM

eh,

not sure about your bugy but mine is at the top rear passenger side of the transfer case.
later,
Pete

Smoke · 03-02-2005, 10:10 PM

Thanks I'll take a look see!!

mburdick · 03-10-2005, 10:02 PM

My '92 was outside the cab, above the transmission. The wires have a coupler out there that was unhooked on mine. If you absolutely can't find it, try pulling the cover off of the floor console and tracing the wire that kind of disappears through the floor.

Smoke · 03-13-2005, 07:44 AM

Thanks will look around for that thing!!

burger · 03-13-2005, 04:24 PM

Smoke,do you have auto- lock hubs?if so,check the vacuum hoses that go to the transfer case and make sure they're both still connected or that they don't have any holes,If they do,it seems like the truck is in 4-wheel,but the light won't come on because things are not working properly-I did some work on my truck and ended up pushing one of the lines against the front axle,wore a hole in the line and had the no light problem.

Smoke · 03-13-2005, 09:19 PM

Thanks burger but I've got the manual hubs!!